Two identical loudspeakers are located at points A & B, 2.00 m apart. The loudspeakers are driven by the same amplifier and produce sound waves with a frequency of 784 Hz. Take the speed of sound in the air to be 344m/s. A small microphone is moved out from point B along a line perpendicular to the line connecting A and B.
(a) At what distances from B will there be constructive interference?
(b) At what distances from B will there be destructive interference?
(c) If the frequency is made low enough, there will be no positions along the line BC at which destructive interference occurs. How low must the frequency be for this to be the case?
The Attempt at a Solution
I'm not sure how to approach this problem. All I know is that constructive interference occurs when the distances traveled by the two waves differ by a whole number of wavelengths, whereas destructive interference occurs when the distances traveled differ by a half-integer number.
Any direction would be greatly appreciated. Thanks!